Signal bond



Jan.. 29, 1924. mmz

J. LUNDE S I GNAL BOND Filed Sept. 25. 1922 Patented Jan. 29, 1924.

UNITED STATES JOHN LUNDE, OF CROOKSTON, MINNESOTA.

SIGNAL BOND.

Application led September 25, 1922. Serial No. 590,532.

To all whom it may camera:

Be it known that I, JOHN LUNDE, a citizen of the United States, residing at Crookston, in the county of Polk and State of Minnesota, have invented certain new and useful Improvements in Signal Bonds, of which the following is a specification.

This invention'relates to means for bonding track rails and fish plates whereby upon breakage in either the rail or the fish plate a signal will be operated to notify a central station of the location of the break and also halt an approaching car or train. The invention is illustrated in the accompanying drawing and will be hereinafter fully set forth. I

In the drawing:

Figure 1 is a side elevation of a portion of a railroad track having my improved bonding means applied thereto;

Fig. 2 is a` transverse section on the line 2-2 of Fig. 1, and

Figs. 3 and 4 are detail views of a bonding terminal.

In the drawing, the reference numeral 1 indicates the meeting ends of alined track rails and 2 indicates fish plates of the usual form Secured to said track ends by bolts 3 and bridging the joint. The bonding members consist of sections of cables 4 consisting of strands of copper wire twisted together to attain strength as well as flexibility, and terminals, each having a tubular body or thimble 6 at one end in which the ends of the cables are received and secured by welding, pinching or other convenient means. The said tubular members 6 are of metal so as to constitute conductors and one end thereof is open to receive the cables, as will be readily understood, while the other end is closed by a head 7 from Which a flat tapered tongue or attaching member 8 projects, it being noted particularly upon reference to Fig. 4 that the attaching tongue 8 is in the same plane with one side portion of the head 7 and the tu- -bular terminal 6 so that an extended flat contact between the terminal and the side of a rail or a fish plate may be obtained.

In applying the bonding members in accordance with my invention, one terminal 5 of each bond is applied against the head of a rail 1 as close to the end thereof as is feasible and is secured thereto by welding,

brazing or some other Iequivalent method whereby a mechanically strong union hav 4minal 5 is Secured against the outer face of the fish plate in the same manner that the first described terminal was Secured to the track rail. The bonding members provide conductors of low resistance whereby the currents flowing through the track rails will be carried from points at the ends of the rails to the fish plates so that, if a break occurs in the rails or in the fish plates, the current will be interrupted and the circuit broken, whereupon the signal at the central station will be operated and the attendants at once notified of the location of the break, the track signal being simultaneously set to close the block in which the break occurs. My device is exceedingly simple, may be readily applied to any rail, and will not be disturbed by the passage of cars or trains over the track, the bonds being located on the outside of the track Where they will not be subject to breakage or disturbance by the car wheel flanges. My invention provides a path of Very low resistance to the flow of the electric current which, otherwise, has a metal path of very high resistance. Owing to rust upon the rails and fish plates, the resistance at various times is suflicient to break the circuit in an unbonded joint, and set the signal at danger When the track is really clear.

Having thus described the iuvention, What is claimed as newis:

The combination with alined rails, and fish plates Secured to and bridging the joint between the rails, of bonding members each consisting of a plurality of strands of copper wire twisted together and terminals mechanically and electrically united with the ends of said wire, one terminal of each bonding member bein electrically and mechanically united wit a rail at the end of the same and the other terminal of the same member being electrically and mechanically united with the adjacent fish plate at the end of the same.

In testimony whereof I aflix my signature JOHN LUNDE. [11.. 3.] 

